Techniques desigled to isolate specific myeloma protein synthesizing polyribosomes by affinity chromatography will be investigated. Extraction of polysomal messenger ribonucleic acid from these polysomes by hybridization to polyuridine filters should provide purified mRNAs for myeloma polypeptide chains. The role of polyadenylate sequences in mRNAs in RNA processing and nuclear release will be investigated with isolated myeloma nuclei in an in vitro transport system. Segregation of discrete mRNAs into specific subpopulations of polysomes (membrane bound versus free polysomes) and control of this mRNA segregation will be studied. Isolated ribosomal subunits and mRNAs of free and membrane bound polysomes will be mixed to assess for functional activity. These studies may suggest which components are responsible for mRNA segregation.